Bearing assembly



May 17, 1960 E. H. ANDERSQN ET AL 2,937,059

BEARING ASSEMBLY Filed April 24. 1958 Fig. l.

Fig. 3.

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BEARING'ASSEMBLY Application April 24, missus... 130. 2

6 Claims. cl. 308-187) The presentinventionrelates to a bearingassembly Patented May 17, lsso in the bearing assembly of this invention.

and more particularly to a bearing assemblywhich can V be used for greasable or prelubricated applications.

For many applications it is desirable to provide .a pre- 7 lubricated bearing assembly, particularly in dynamo-electric machines. These bearing assemblies are designed to last for the life of the machine without further need for lubricating them. Double seals are provided which extend between the races on each side of the bearing to prevent leakage of grease or other lubrican't from .the hearing as well as to prevent contamination of thelubricant .by foreign particles and ,dust which may be drawn in to the machine as it breathes. During the operation of the dynamo-electric machine, the temperature of the machine varies in accordance with the load. Con- 'sequently, the air pressure in the machine housing fluctuates and the machine breathes. When the machine is heavily loaded, its temperature rises so that airpressllre Fig. 2 -is a longitudinal sectional view of the bearing assembly taken on line II-II of Fig. 1 in which the cap -is mounted in the prelubricated position, and

I Fig. 3 is a longitudinal sectional view of the bearing assembly of this invention taken on line II-II of Fig. "1 with the cap'mounted in a greasable position. 7

Refering now particularly to Figs. 2 and 3, there is shown a bearing bracket and bearing assembly for a dynamo-electric machine. A bearingbracket 10 is shown as a hollow cylindrical member open at its ends having an annular flange 12 on its outermost end which forms a shoulder 14 extending from the inner surface of the hearing bracket. A grease inlet opening 16 and a grease outlet opening 18 are bored radially through flange 12. An

air by-pass opening 20is formed in bearing bracket 10 and extends from the inner surface of flange 12radially in the housing alsorises. If the load is decreasedor thev machine switched oin-the temperature falls so that air pressure in the casing is decreased and air is expirated into the casing through the bearing. As a result, dust particles are likely tobe drawn into the hearing andlubricant is sucked fromthe bearing into the machinehousing. The aforementionedseals prevent thefouling'of the lubricant due to breathing.

In this type of bearing assembly, an air by-pass through i the bearing bracket is provided to permit breathing although the bearings are sealed. 7

For certain applications ,a sealedpre-lubricated bearing assembly is desirable. Such an arrangement eliminates the possibility of over-greasing and under-greasing.v

Further advantages are apparent when the motor is located in a position where it is diflicult to reach ,for greasing or in an extremely contaminated area;

Under certain conditions, "however, itis more desirable to provide a'bearing assemblywhich can be lubricated from time to time. For example, when a machine is run continuously for long periods of time, perhaps daily or weekly, the original lubricant may require flushing" and replacement. For various reasons it maybe advan-' tageous to provide a greasable bearingassembly. Present- 1y known bearing assemblies are either prelubricated or and then proceeds longitudinally through the wall of bearing bracket 14. A ball bearing 22 having an inner race 24 and an outer race 26 is received in the bearing bracket '10. By way of example, anti-friction member s between theinner race and outer race are shown as balls 28, but it will be, of course, understood that any suitable anti-friction member may be used, as for example rollers. Outer race 26 of bearing 22, is formed with an annular notch 30 adjacent each end. Notch 30 has a radially extending side wall and a longitudinally extending side wall perpendicular to the radially extending wall., A pair of inner seals 32 are secured to the radially extending walls of notch 30 in any suitable manner and extend radially inwardlytoward the inner race.2 4 of bearing 22. A pair of outer annular seals 34 are secured in any suitable manner to the inner race 24 of ,bearing22'and extend radially outward toward outer the races l tand 2 6. .Prior to securing the'sealsto the bearing 22, thebearing is filled with a suitable lubricant.

greasable and cannot beconverted from one to the other. 1

It is often necessary to transfer a machine fromfone type of service to another. The new application; of the machine may necessitate changing from a prelubricated hearing to one that can be lubricated. Furthermore, one user may require machines of each type for different applications requiring them to stockdiflerent replacement parts for each. I

It is, therefore, an object of this invention to provide The seals 32 and 34am secured'in such .a manner as to be readily removable if desired.

ing,2 2 ,'The shaft 36 has a reduced end portion 38 forming a shoulder 40 which bears against the inner end of the inner race. The outer end of theouterrace 26 "bears againstshoulder 14 of flange 12. Inner race 24 small clearance between the shaft 36 and the bearing cap 42. Bearing capl42 ihasan annular flange 46 extending radially outwardand an annular flange 48extending lonof flange '48 abuts the inner periphery of flange .12 and a bearing assembly which can'be utilized either as a prelubricated bearing assembly or as a greasable assembly.

Another object of this invention is to provide a bearing assembly of the pre -lubricated type which includes gitudinally inward. Flange' ifi abuts the outer end of extends inwardly beyond the openings 16, 18 and 20.

elements for converting it to a greasable hearing ss 'sembly.

,A pair of ears Y48 and 50 aresecured integrallywith flange 46 and at diametrically opposite positions on-the ra Ea s 4 n .50 havebQl receiving openingswhich correspond to and are in alignment with A rotatable shaft 35 is received and supported in bear- 3 bolt receiving openings on bearing bracket 10. The bearing cap 42 may be secured to the. bearing bracket 111 any suitable manner as for example, by bolts 52 and 54 passing through bolt receiving open-ing in ears 48 and 50 and threaded in bolt receiving openings in the bearing bracket 10. Flange 48 on bearing cap 42 have formed therethrough notches 56, 58 and 60 as can best be seen in Fig. l. Notches 56 and 58 are each circumferentially spaced from notch 60 a distance equal to the'distance between the grease inlet 16 and grease outlet 18. The notches 56, 58, and 60are further positioned relative to bolts 52 and 54 so that when the cap is mounted in one position on the bearing bracket '10, notches 56 and'58 will be out of alignment with grease inlet 16 and 18wvhile notch 69 will be aligned with air by-pass opening 20. The bolts 52 and 54 may be removed from the cap 42 which may be rotated through 180 thereby mounting the cap with bolt 52 in car 50 and bolt 54 in ear 48. In this case openings 56, 58 and 60 are so arranged that notch 60 and either notch 56 or 58 will be in alignment with grease inlet 16 and grease outlet 18, respectively, and none of the notches 56, 58 or 6% will be in alignment with air by-pass opening 20.

When none of the notches 56, 58 or 60 are in alignment with openings 16 and 18, the bear-ing assembly described is a prelubricated bearing assembly which requires no lubrication from time to time. The lubricant in the hearing will last for the life of the machine under most operating conditions. In this condition the air by-pass opening 20 being in alignment with notch 60 permits the motor to breathe, the air leaving the motor housing through the by-pass opening 20 and notch 60 and out through the clearance between the bearing cap and the shaft. Air may also be drawn in through the clearance between the shaft and opening 44 and enter the housing through the notch 60 and by-pass opening 20 without passing through the bearing. The seals and 32 prevent any contaminants that may be contained in the air from entering the bearing and also the lubricant from being drawn out of the bearing into the housing.

If it .is desired to utilize the assembly as a greasable assembly which can be lubricated from time to time, bolts 52 and 54 may 'be removed. The bearing cap 42 may be rotated through 180 and the bolts 52 and 54 may be reinserted to secure the bearing cap 42 to the bearing bracket 10. In this position the notches 60 and 56 are in alignment with grease inlet opening 16 and grease outlet 18, respectively. Air by-pass opening 20 is closed. In this case, the outer seal 30 on the outer end of hearing 22 may be removed to permit entry of lubricant between races. Seals 30 and 32 on the inner end of the bearing will prevent the lubricant from being drawn into the motor housing. In this application of the bearing assembly the air by-pass opening 20 is closed. This is necessary to prevent lubricant which is introduced into lubricant inlet 16 from passing through the by-pass opening 20 into the machine housing. Outlet opening 18 is opened to permit escapement of excess lubricant.

In the embodiment illustrated in the drawings notch 56 is utilized to provide an opening for grease outlet 18 when notch 69 is in alignment with grease inlet 16. Notch 58 is an auxiliary notch provided to increase the versatility of the bearing cap 42. It may sometimes be necessary to locate the grease outlet opening 18 in the opposite side of the machine. This may become necessary because of the location of the machine'in a position where the grease outlet would be inaccessible if it were located as shown in Pig. 1. In'such a case auxiliary notch 58 would be utilized to provide an opening for grease outlet 18 while notch 56'would become an alternative or auxiliary opening.

It will now be apparent that a new type of bearing assembly has been provided which is very versatile in its applications.

to a dynamo-electric machine but it will be, of course,

It is illustrated and described as applied lubricated applications thus, permitting more economical production on a larger scale. A single set of replacement parts is required for eitherv application. The user may convert the machine from one type of service to another in a simple manner. 7

A specific embodiment of the invention has been shown and described for the purpose of illustration but it will be understood that various other embodiments and modifications are possible and are within the scope of invention.

We claim as our invention:

1. In a bearing assembly for a dynamo-electric machine, a substantially cylindrical bearing bracket open at its ends having a lubricant inlet opening, a lubricant outlet opening and an air by-pass opening, a cap for closing the outer end of said bracket, means for mounting said cap in a first position to open said grease inlet and outlet openings and to close said air by-pass opening, means for mounting said cap in a second position to close said grease inlet and outlet openings and to open said air by-pass opening, means for selectively securing said cap in said first or said second position, whereby said bearing assembly may be converted from a prelubricated hearing assembly to a greasable assembly.

2. In a bearing assembly for a dynamo-electric machine, a substantially cylindrical bearing bracket open at its ends having a lubricant inlet opening and a lubricant outlet opening, said openings extending radially outward from the inner surface of said bracket, 2. cap for closing the outer end of said bracket having an annular flange extending axially inward beyond-said bracket openings and lying adjacent the inner surface of said bracket, said flange having circumferentially spaced passages extending radially therethrough, securing means circumferentially spaced degrees for mounting said cap on said bracket, said passages being in alignment with said openings when said cap is mounted in a selected position and out of alignment with said openings when said cap is mounted in a position rotated 180 degrees from said selected position.

3. A bearing assembly for a dynamo-electric machine comprising a substantially cylindrical bearing bracket open at its ends having a lubricant inlet opening, a lubricant outlet opening and an air by-pass opening, said openings extending radially outward from the inner surface of said bracket, a cap for closing the outer end of said bracket having an annular flange extending axially inward beyond said bracket openings and lying adjacent the inner surface of said bracket, said flange having first and second circumferentially spaced passages extending radially therethrough, securing means circumferentialiy spaced 180 degrees for mounting said cap on said bracket, said first and second passages being in alignment with said lubricant inlet and outlet openings, respectively, when said cap is mounted in a selected position, said first passage, being in alignment with said air by-pass opening when said cap is mounted in a position rotated 180 degrees from said selected position.

4. A bearing assembly for a dynamo-electric machine comprising a substantially cylindrical bearing bracket open at its ends having a lubricant inlet opening, a lubricant outlet opening and an air by-pass, said openings extending radially outward from the inner surface of said bracket an anti-friction bearing supported in said bearing bracket, removable seal means on said antifriction bearing for retaining lubricant in said bearing, a cap for closing the outer end of said bracket, means on said cap for selectively opening or closing said openings,

means for mounting said cap to selectively open said lubricant openings and-close saidby-pass opening or to close said lubricant openings and close said by-pass opening, whereby said bearing assembly may be converted from a prelubricated bearing assembly to a greasable bearing assembly. V i A bearing assembly for a dynamo-electric machine comprising a substantially cylindrical bearing bracket open at its ends having a lubricant inlet opening and a lubricant outlet opening, said openings extending radially outward from the inner surface of said bracket, an antifriction bearing supported in said rbearing bracket, re-

inovable seal means on said anti-friction bearing for retaining lubricant in said bearing, a cap for closing the outer end of said bracket having an annular flange extending axially inward beyond said bracket openings and lying adjacent the inner surface of said bracket, said flange having circumferentially spaced passages extending a radially therethrough, securing means circumferentially spaced 180 degrees for mounting said cap on said bracket, said passages being in alignment with said openings when said cap is mounted in a selected position and out of alignment. with said openings when said cap is mounted in a position rotated 180 degrees from said selected position. i

6. A bearing assembly for a dynamo-electric machine comprising a substantially cylindrical bearing bracket open at its ends having a lubricant inlet opening, a lubricant outlet opening and an air by-pass opening,

said openings extending radially outward from the inner surface of said bracket, and an anti-friction bearing supported in said ,bearingbracket, removable seal means on said anti-friction bearing for retaining lubricant in said bearing, a cap for closing the outer end of said bracket having an annular flange extending axially inward beyond said bracket openings and lying adjacent the inner surface of said bracket, said flange having first and second circumferentially spaced passages extending radially therethrough, securing means circumferentially spaced degrees for mounting said capon said bracket, said first and second passages being in alignment with said lubricant inlet and outlet openings, respectively, when saidcap is mounted in a selected position, said first passage, being in alignment with said air by-pass' opening-when said cap is mounted in a position rotated 180 degrees from said selected position.

- References Cited in the file of this patent UNITED STATES PATENTS 1,216,031 Wilcox Feb.'13, 1917 

